Day: December 8, 2009

We received an excited email from [Noah] regarding a gentleman who works with crossbows and crossbow pistols. Begrudgingly, we took a look and what we saw made our day. [TheDuckman666] must have an insatiable love for all things crossbow. His webpage has details and pictures covering seven different models that he built. His YouTube channel shows off three more models, all with magazines for multiple bolts.

Seeing the electrically-cocked, automatic projectile launchers wets our appetite, but we do wish there was more background info about the build process.

It’s not the finished product that interests us, but the methods he used to create such a nice looking enclosure. From the wooden binary adder he produced we know he’s a talented woodworker. He takes us step-by-step through the use of a scroll saw, table saw, and router tabled to turn out this one-of-a-kind. You may not own these tools but someone you know does. Follow his example and turn out your own wooden wonders.

What do you do if you can’t find the film that your camera uses? The answer seems pretty simple, you just make it yourself. Making film is not a simple task. There are multiple stages involved and it all has to be done in complete darkness. This project is causing a bit of stir in its respective communities. Though not completely finished yet, it is already an impressive piece. Everyone is waiting eagerly for it to be completed. You can find a few of the discussion groups linked from the flickr page.

While this is most likely overkill for a gas gauge, we do thank [VadimS] for sharing the information. He shows us how to build a capacitive liquid sensor using an Arduino, some foil and some wire. He’s basically detecting the difference in capacitance between the foil sheets. As he gets more water in the bottle, the capacitance goes up. At least we think thats what is going on. He has included the source code for the Arduino, both for handling the sensor and running the LCD display shown in the picture above. When completed, this will be used in his dune buggy for a gas gauge.

It’s hard to believe that in five years we haven’t covered lifters before. This realization was sparked when [Tyler] tipped us off about a lifter project demonstrated at the Kansas City hackerspace called CCCKC.

Lifters, the casual name for ionocraft, fly without combustion or moving parts. We’re not going to tackle the particulars of what makes flight possible, but high voltage is required to feed the phenomenon that provides the lift. One of the first comments when we asked what to do with old CRT monitors was to use them for lifters. The flyback transformer puts out plenty of voltage if you can tap into it without killing yourself (no, seriously, that’s an issue).

This is the method that the CCCKC folks used. Take a peek at the video after the break. If you’re thirsting for more fun with lifters, stop by the Lifter Project.

Well no, but [Chris] needed something to remind him when to water the tree. Most folks would use their nifty iPhone to set up a calendar reminder, but why do that when you can purpose a 32 bit microcontroller to do it for you?

To detect a falling water level [Chris] attached a two-pin header to the end of a clothes pin clipped to the side of the tree stand. When the water level is covering the pins it completes a circuit, verified by a measurable current. When the water level drops the mbed microcontroller detects the loss of conductivity and through some creative code sends out an email and SMS reminder.

If you’re in love with your iPhone but not your living things, this will keep that tree kicking until after the new year.